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JRA01: ACTAR. Task J01-1: Physics constraints and detailed simulations Subtask J01-1-1: Physics constraints Subtask J01-1-1: Simulations Task J01-2: Test modules Subtask J01-2-1: detection/target gas Subtask J01-2-2: Readout chamber Subtask J01-2-3: Magnetic field configuration
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JRA01: ACTAR Task J01-1: Physics constraints and detailed simulations Subtask J01-1-1: Physics constraints Subtask J01-1-1: Simulations Task J01-2: Test modules Subtask J01-2-1: detection/target gas Subtask J01-2-2: Readout chamber Subtask J01-2-3: Magnetic field configuration Task J01-3: Electronics and data acquisition Task J01-4: Particle tracking
Task J01-1Physics constraints and detailed simulations Subtask J01-1-1: Physics constraints Task leader: B. Blank White paper achieved in November 2005 available via ftp://ftpcenbg.in2p3.fr/pub/nex/ACTAR Subtask J01-1-1: Simulations Task leader: D. Cortina Framework constructed, first simulations performed
Overview of ActarSim H. Alvarez Pol USC
Physics constraints and simulations 2 main questions: Cubic or Cylindrical geometry? Magnetic field or not? — Large dynamics needed: 0.2-20 MeV — Either magnetic field or ancillary detectors (many) — Energy resolution: 50 keV for Si detectors =>10% at 0.5 MeV, 0.5% at 5 MeV Position resolution 0.25mm =>2.5% for 1cm, 0.25% for 10cm —Cubic geometry : Problem with deflection of the beam with B Solid angle reduced by factor 2(4) —Cylindrical geometry: Problem at small angles (ancillary detectors below 5°) Varying rise times of the pulses —Preliminary simultations in favor of cylindric geometry with longitudinal electric and magnetic field for reactions related to resonant elastic scattering, inelastic scattering (giant resonances) and transfer reactions.
Definition of geometry for the next generation active target Cylindrical geometry: symmetry around beam axis E // beam axis, uniform Projection on the endcap of the cylinder B // beam axis Anode ASIC cards Pads Cathode 13 Altro boards 128 channels 20x200 mm (including cooling) 1664 channels/quarter R 300 Solenoid limit Active area R 7.5 – 250 O 50cm 50cm Gangnant@ganil.fr rosier@ipno.in2p3.fr Quantities to be measured: curvature radius, collected charge, range, angles For 0.5 mm position resolution, E/E=2R/R, expected energy resolution≈100 keV for cm>20°
Simulations : 78Ni(d,p)79Ni cm=20° Ex=0,1.5,3 MeV Einc= 8.5 A.MeV D2 at 1atm Xreac= 5 cm B=2 T Ex = 0, g.s. Ex = 1.5 MeV Ex = 3 MeV Hector Alvarez-Pol, Esther Estevez-Aguado, USC
Task J01-2Test modules Subtask T-J01-2-1: detection/target gas Subtask T-J01-2-2: readout chamber Subtask T-J01-2-3: magnetic field configuration For subtasks 1 and 2: Three test modules within ACTAR: Bordeaux TPC (B. Blank et al) using GEMS MAYA (W. Mittig, H. Savajols) and MAYAITO (F. Rejmund, A. Villari), both at GANIL and using wires Contact established with TACTIC group (York, TRIUMF) New test module under construction in collaboration with IPN Orsay and LAL for MICROMEGAS
TPC for 2p radioactivity studies Bertram Blank, CENBG
TPC for 2p radioactivity studies 1500 electronics channels GEM: Gas electron multiplier beam Hybrid boards Hybrid boards Daughter boards Daughter boards
TPC for 2p radioactivity studies Detector mount Detector mount TPC chamber Electronics card Strip-strip matrix GEM = 70mm d = 100mm
y Implantation at end Implantation at entrance saturation x Silicon detector beam x energy | x time|yenergy| y time TPC: implantation events 48Ca + 9Be 26P, 25Si,…. Threshold for implantation events Threshold for radioactivity events End of TPC Center of TPC Entrance of TPC Different implantation depths by changing the Br
y b-delayed decay Collimated a source x Silicon detector beam x energy | x time|yenergy| y time b-delayed decay TPC : Decay events b-delayed decay
MAYA-ITO test runs at GANIL F. Rejmund et al.
MAYA-ITO test runs at GANIL Beams used 13C @ 3 - 4.35 - 11MeV/u 16O @ 3.4 - 8.4 MeV/u 36S @ 3.92 - 11.32 MeV/u 208Pb @ 4.5 MeV/u Gases: H,D,He,Ne,Ar,Xe, Isobutane
TRIUMF Annular Chamber for the Tracking and Identification of Charged Particles Original concept: L. Buchmann, TRIUMF TACTIC: York-TRIUMF Collaboration
How is it going to work? • 90% helium 10% CO2 gas mixture • Pressure of a few hundred mbar • Drift voltage ~100V/cm
Task J01-3Electronics and Data acquisition Evaluation of existing ASICs 3 chips can fulfill the requirements for active targets: — GASSIPLEX (used in MAYA and MAYAITO) — ALTRO (developed for ALICE TPC) — T2K (developed for T2K experiment) Test module under construction in collaboration with Orsay will allow to test ALTRO in 2007 and T2K in 2008
T2K ASIC (Tokai to Kamioka) L.Pollacco
ALTRO for ALICE TPC Read-out chamber ADC 10bits 10 & 40 MHz Power hungry (35 mW/channel)
JRA 01 Milestones LoI presented at the SPIRAL2 SAC Meeting, October 2006 « Direct reactions with an active target » Spokerpersons: M.Chartier, D. Cortina, P. Roussel-Chomaz SAC recommendations received November 29th
JRA 01 Budget Ganil Bordeaux Saclay CCLRC Liverpool USC GSI Remarks -France: all budget for personnel has been given to GANIL which redistributes to Bordeaux and Saclay. One postdoc starts at Bordeaux on December 15th for 9 months. Saclay will have 8 months in 2007. -Spain (USC):one sudent has also started -GB (Liv+Daresbury): a large fraction of budget spent Remark: ACTAR probably extended until the end of Eurons (instead of end 2007)
TPC for 2p radioactivity studies Detector: double-sided microstrip detector (CERN) GEM: Gas electron multiplier (CERN) Detector gas: P10 at 1atm Active detection volume: 15 x 15 x 15 cm3 ASICS: VAT/TAT by IDEAS, Norway TAC window: 10 s channels per chip: 32 time and energy Electronics and data acquisition: PXI – VME Dead time: 1.5 ms (max) Problems - up-grades 4 GEMs to increase the gain new a source collimation system non-linearity of the gain (-30% on sides) retract drift frames Successful experiment in September 2006